Three men, aged 67 years, 80 years and 53 years, respectively, developed signs and symptoms of progressive right-sided heart failure following open heart surgery. They were diagnosed with constrictive pericarditis based on echocardiography, cardiac magnetic resonance and cardiac catheterisation. Following pericardiectomy, two of the patients fully recovered, while one, the 80-year-old man, died during convalescence. When signs and symptoms of progressive right-sided heart failure develop after open heart surgery, a diagnosis of constrictive pericarditis should be considered. Constrictive pericarditis after open heart surgery may be caused by inflammation of the pericardium; an old, fibrotic haemopericardium, which may be diffuse or loculated; pericardial adhesions; or a combination of these entities. Diagnosing constrictive pericarditis is difficult and may take a long time. However, it is important to recognise this disorder early before it has progressed to an advanced stage. Pericardiectomy is the only effective therapy. When performed too late, survival is significantly reduced.